it would be that ur tyre is rubbing on the guard. If u have lowered ur car alot then that would be the reason. If u are still running on the stock springs they probally are shot, and i would advise getting new harder springs, this would also improve the steering. If u want to lower it from stock ride height this would be a good chance to do it, but don't lower it too much as the copper don't like that and will get out the ruler on u.
Remember to get ur wheels alined once u have the new springs in or u will go through tyres faster than u should.